Alfred pushes on a heavy box, but cannot move it. the box has a lot of inertia motion friction gravity

Inertia

Explanation:

Inertia is best defined as the ability of an object to resist a change in position or movement. That is why when an object has a higher mass, the higher the inertia. Imagine an oncoming truck that is fully loaded versus you. The tendency for the truck to change its movement would be difficult because of its its mass. It has a lot of inertia.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia